bike shop switched cassettes on me

[awm03]

DH took my 20 month old bike in for a tune-up. The mechanic told DH it needed a new chain (ok...) and a new sprocket ( ). My husband gave him the go ahead for the work. Got the bike back today, and the biggest sprocket in the new cassette is only 23 teeth. The old one had 25. I really need at least 25 to climb hills around here.

I will take the bike back and ask them to switch out the cassette. But just curious: how many teeth on your big sprocket? And isn't it strange that a cassette needs replacing after 20 months? Old one was a Shimano, new one is SREM, if that makes a difference.

Thanks for your input.

[Veronica]

Replacing is really about distance more than time. My largest cog is a 27.

V.

[madisongrrl]

Road bike = double up front, 12-27 rear

Mountain bike = triple up front, 11-31 rear

[maillotpois]

You may mean SRAM?

I have to replace a cassette every year at least (after every second chain change usually) - and I take pretty meticulous care of them, including taking them off and cleaning them in the ultrasoinic cleaner every month or so - so I think I suck all the life out of them that I can.

I think I have a 29.

[yellow]

Yeah, miles. It very well may have needed replacement, esp if your chain was overdue. The cassette will "mate" the the chain; it's not uncommon for it to need replacement at the same time as the chain. I usually replace each once a year (chain twice, usually).

However, they should have told you that they were switching the 25 for a 23. They most definitely need to know about that "mistake". It may very well be that the 12-25 cassettes are hard to get in stock (that was certainly the case last year with the 12-27 cassettes, which is what I ride).

MP, you have a 29??? (I'm jealous!) Which rear derailleur do you have? Are you on a double?

[maillotpois]

Yellow - I have campy triple, 10 speed. I think it's 13-29. Don't use it much, but it's nice to have. (Remember, Amazon-like girl who likes to do things like the Death Ride.)

Now, I would like something bigger in front.... maybe a 55...

[Veronica]

A 55! Yikes! I hardly use my 48. But I'd like that 29 in the rear!

V.

[awm03]

Thanks for your responses. They're very helpful. I think the mechanic in the bike shop assumed the road bike was my husband's and the mtn. bike was mine, and that of course DH would want something that delivered more speed.

This leads to a second question: do you think bike shops don't take you seriously? I'm 51, overweight*, & getting gray-haired. Seems like the young things at the bike shop aren't too interested in my biking needs. I've been biking over 30 years, and I *know* a 23 cog ain't gonna cut it for me. Betcha they'll try to talk me into it because they'll assume I don't know what I'm talking about.

*but losing! Lost 26 lbs. so far.

[Geonz]

They're probably used to their 'comfort level' of categories of people, and you don't fit... so just keep expanding their horizons. They're young critters :-)

[jobob]

Road bike = double up front, 12-27 rear

Mountain bike = triple up front, 11-31 rear

No. You're over-generalizing.

My road bike has a triple up front and a 12-27 in the rear.

My other road bike has a triple up front and a 13-32 in the rear.

[SadieKate]

Mtbike rear cassettes are frequently as large as 34T.

The combos of chainrings and numbers of teeth are infinite. Bottom line is they shouldn't change cassette size on you without your agreement.

[jobob]

Absolutely. They should have replaced it with the same size cassette. Don't just *ask* them to put a 25t cassette back on, tell them.

[maillotpois]

A 55! Yikes! I hardly use my 48. But I'd like that 29 in the rear!

V.

I've got a paltry 50 or 51, and I spin out on long, flatter descents where I really want to grind. When we were in France one year for the Tour we saw into the iBanesto team bus and they had these rows of dinner plate sized rings.... drool!

The 29 is great. I'm actually looking to get a spare 11-27 to give me a little more oomph when I do flatter rides like the Tucson race.

[barrb46]

Hi AWM,
I just had my cassette and chain replaced -- and the shop said it is common to need to replace it when you have around 3000 miles on the bike. I have 2900 on my bike. I also had the derailler replaced, since apparently somehow it was damaged. Cost $50 for the cassette and chain. $45 for the rear cassette which was an exact replacement of the one on it.

I trust this bike shop 100% and was having some shifting problems, so I feel they were not "taking me for a ride".

How many miles have you ridden with this bike?

Barb

[CorsairMac]

I have 33/43/53 Biospheres up front and 27-11 in back. I just replaced my chain and cassette and they put on exactly what they took off. He counted the cogs in back to make sure the new cassette matched the old one.